Features and Advantages
PPM Purge Bag System
Sizes: 2 to 24″ (50 to 610mm)
Double Inflatable Pipe Weld Purging Systems
Due to the design of these systems, the volume of gas used to purge is minimised, resulting in significant savings in both time and the quantity of inert gas used.
Return on investment can be achieved in as little as just one or two welds.
These robust systems can be used over and over again paying for themselves in very little time.
- PPM’s Inflatable Pipe Purging Systems dramatically reduce purging times leading to significant savings in labour costs
- Typical purge times for 4″ pipe = 1½ mins; 8″ pipe = 4 mins; 12″ pipe = 8 mins
- Ready to use, connects to a dedicated and regulated gas supply. Choose any flow rate up to 20l a min. Through the pre-set purge valve
- Gas pressure control ensures an even positive root bead with no notching
- Quick and easy to install simplifying the process of inert gas purging
- Heat resistant up to 70ºC continuously
- Use less inert gas. The volume of purge gas used is less than 2% of that required for a conventional purge
How it works
The Purge Bag Systems in the range manufactured by PPM are designed around the principle of using 2 dams to create a seal either side of the weld, just far enough away from the weld not to be effected by heat but close enough to the joint to provide the fastest weld purge time.
These dams are connected by an armoured spinal tube.
Once ready to start purging, the system is inserted into the bore of the pipe using the luminous strip to centre the system to the weld gap.
When the gas flow is started, the dams inflate and, upon reaching the pre-set pressure, the valve releases the gas gently into the weld chamber, to purge the interspace without turbulence.
The Oxygen is removed from the weld chamber through the integral exhaust tubes in the bags.
Used in conjunction with PPM’s Oxygen Monitors to indicate when the required low level of oxygen has been reached, welding can then commence, with the inert gas enabling the welder to produce an even oxidation free penetration weld bead.
Afterwards, the dams are deflated simply by disconnecting the purge gas feed and the system easily withdrawn.
The design of these systems means that only one gas connection is required for both dam inflation and weld purging.PPM Purge Bag System PDF